One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,5,7,8)(9,10)(11,15)(12,20)(13,14)(16,21)(17,19)(18,23)(22,24)(25,26,32,36)(27,37,39,33)(28,29,30,34)(31,35,38,40)(3,7)(5,8)(9,10)(11,17)(12,20)(13,14)(15,19)(16,21)(18,22)(23,24)(25,27)(26,33)(28,35)(29,31)(30,40)(32,39)(34,38)(36,37) involution — undirected(1,2)(3,5)(4,6)(7,8)(10,14)(15,17)(16,20)(22,23)(25,28,32,30)(26,34,36,29)(27,35,39,40)(31,33,38,37)(1,3)(2,5)(4,7)(6,8)(9,11)(10,15)(12,18)(13,19)(14,17)(16,22)(20,23)(21,24)(25,29)(26,28)(27,38)(30,36)(31,39)(32,34)(33,40)(35,37) involution — undirected(1,2)(3,5)(4,6)(7,8)(9,12)(10,16)(11,18)(13,21)(14,20)(15,22)(17,23)(19,24)(25,30,32,28)(26,29,36,34)(27,35,39,40)(31,33,38,37)(9,10)(11,15)(12,16)(13,14)(17,19)(18,22)(20,21)(23,24)(25,31,32,38)(26,35,36,40)(27,29,39,34)(28,37,30,33)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.